title: Evaluation of a new experimental model to study bone healing after ridge expansion with simultaneous implant placement--a pilot study in minipigs.
abstract: OBJECTIVE
  To evaluate the suitability of a minipig model for the study of bone healing and osseointegration of dental implants following bone splitting and expansion of narrow ridges.
  
  
  METHODS
  In four minipigs, the mandibular premolars and first molars were extracted together with removal of the buccal bone plate. Three months later, ridge splitting and expansion was performed with simultaneous placement of three titanium implants per quadrant. On one side of the mandible, the expanded bone gap between the implants was filled with an alloplastic biphasic calcium phosphate (BCP) material, while the gap on the other side was left unfilled. A barrier membrane was placed in half of the quadrants. After a healing period of 6 weeks, the animals were sacrificed for histological evaluation.
  
  
  RESULTS
  In all groups, no bone fractures occurred, no implants were lost, all 24 implants were osseointegrated, and the gap created by bone splitting was filled with new bone, irrespective of whether BCP or a barrier membrane was used. Slight exposure of five implants was observed, but did not lead to implant loss. The level of the most coronal bone-to-implant contact varied without being dependent on the use of BCP or a barrier membrane. In all groups, the BCP particles were not present deep in the bone-filled gap. However, BCP particles were seen at the crestal bone margin, where they were partly integrated in the new bone.
  
  
  CONCLUSIONS
  This new minipig model holds great promise for studying experimental ridge splitting/expansion. However, efforts must be undertaken to reduce implant exposure and buccal bone resorption.
authors.affiliation: Department of Oral and Maxillofacial Surgery, University Hospital of Freiburg, Freiburg, Germany.
authors.forename: Andres
authors.initials: A
authors.lastname: Stricker
authors.affiliation: Oral Imaging Center, Faculty of Medicine, Katholieke Universiteit Leuven, Leuven, Belgium.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Fleiner
authors.affiliation: Department of Periodontology and Implant Dentistry, New York University, New York, NY, USA.
authors.forename: Michel
authors.initials: M
authors.lastname: Dard
authors.affiliation: Department of Oral and Maxillofacial Surgery, University Hospital of Freiburg, Freiburg, Germany.
authors.forename: Pit
authors.initials: P
authors.lastname: Voss
authors.affiliation: Department of Oral and Maxillofacial Surgery, University Hospital of Freiburg, Freiburg, Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Sauerbier
authors.affiliation: Department of Oral Surgery and Stomatology, School of Dental Medicine, University of Bern, Bern, Switzerland.|Department of Periodontology, School of Dental Medicine, University of Bern, Bern, Switzerland.|Robert K. Schenk Laboratory of Oral Histology, School of Dental Medicine, University of Bern, Bern, Switzerland.
authors.forename: Dieter D
authors.initials: DD
authors.lastname: Bosshardt
mesh_terms: D000540:Alveolar Ridge Augmentation / Q000379:methods*; D000818:Animals; D015519:Bone Density / Q000502:physiology; D001861:Bone Regeneration / Q000502:physiology; D018786:Bone Substitutes / Q000627:therapeutic use; D000069343:Bone-Implant Interface / Q000033:anatomy & histology; D003758:Dental Implantation, Endosseous / Q000379:methods*; D005260:Female; D048091:Guided Tissue Regeneration / Q000379:methods; D006882:Hydroxyapatites / Q000627:therapeutic use; D008334:Mandible / Q000601:surgery*; D008567:Membranes, Artificial; D023421:Models, Animal; D016348:Osseointegration / Q000502:physiology; D010012:Osteogenesis / Q000502:physiology; D010027:Osteotomy / Q000379:methods; D059745:Piezosurgery / Q000379:methods; D010865:Pilot Projects; D011897:Random Allocation; D013552:Swine; D013556:Swine, Miniature; D013997:Time Factors; D014945:Wound Healing / Q000502:physiology
chemical_list: D018786:Bone Substitutes; D006882:Hydroxyapatites; D008567:Membranes, Artificial; C074950:hydroxyapatite-beta tricalcium phosphate
keywords: biphasic bone substitute; bone regeneration; bone splitting/ridge expansion; minipig; osseointegration